BOULDER—Two DOW (Doppler on Wheels) mobile radars have
arrived near
Mobile, Alabama, and are being readied to intercept the eye of
Hurricane
Ivan as it hits land. The radars will collect unprecedented
high-resolution Doppler radar data and wind measurements from inside
the
storm. Josh Wurman, director of the DOW program of the Center
for Severe
Weather Research (CSWR), is on site near Mobile and available by
cell
phone to speak with reporters, as conditions allow.

By scanning inside a hurricane’s eye, the DOWs can see intense
storm
features as small as 40 feet across, resolving very small-scale
but
potentially damaging wind streaks, gusts, and other structures.

The DOWs are operated by the CWSR, based in Boulder, and were
developed
in partnership with the National Center for Atmospheric Research
(NCAR).
The radars are primarily supported by the National Science Foundation
(NSF).

The new rapid-scan Doppler on Wheels unit
tracks a storm.

The two advanced mobile Doppler radars are mounted on hardened
truck
beds constructed to withstand the rigors of the hurricane environment,
including winds over 130 miles per hour and airborne debris. They
have
intercepted the eyes of seven hurricanes: Fran, Bonnie, Floyd,
Georges,
Lili, Isabel and, and, most recently, Frances. Frances was the
first
hurricane in which the DOWs were able to observe direct onshore
wind
flow over the water from ranges as low as 100 meters (about 330
feet).

Last year, in the throes of Hurricane Isabel, the DOWs collected
the
highest-ever resolution in multiple-Doppler data from a hurricane.
The
data resulted in the discovery of an entirely new phenomenon in
hurricanes, called intense boundary layer rolls, which contain
the
highest and most dangerous wind gusts, with the potential to cause
the
most damage.

The DOW radars have revolutionized the study of tornadoes and
other
violent and small-scale atmospheric phenomena, according to CSWR
director Josh Wurman. DOWs have measured the highest wind speeds
ever
recorded near Earth’s surface: 301 mph in a tornado. They
have been
deployed in wide-ranging research environments, including wild
fires,
homeland security experiments, aviation-related turbulence, winter
weather, birth of storms, mountain weather in the Alps, and 20
other
projects in recent years.

The National Center for Atmospheric Research and
UCAR Office of Programs are operated by UCAR under the sponsorship
of the National Science Foundation and other agencies. Opinions,
findings, conclusions, or recommendations expressed in this publication
do not necessarily reflect the views of any of UCAR's sponsors.